A tanker traveling along a highway rolled and leaked toxic chemical phenol into a river in east China's Zhejiang Province late Saturday night, local authorities said on Sunday.

The chemical substance spilled out of the tanker and was washed by heavy rain into the Xin'an River at about 11 p.m. Saturday, said a spokesman for the publicity office of Jiande City where the accident occurred.

Xin'an River, which feeds into the Fuchun and Qiantang rivers, is the source of drinking water for several cities in Zhejiang, including the capital city of Hangzhou.

The local environment protection authorities are working to contain the pollution, the spokesman added.

Phenol and its vapors are corrosive to the eyes, skin and respiratory system. Skin contact with the substance may cause burns. It can also harm the central nervous system, heart, lung and kidney.